Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
  • G01R31/385—Arrangements for measuring battery or accumulator variables
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
  • G01R31/385—Arrangements for measuring battery or accumulator variables
  • G01R31/386—Arrangements for measuring battery or accumulator variables using test-loads
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
  • G01R31/389—Measuring internal impedance, internal conductance or related variables
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
  • G01R31/382—Arrangements for monitoring battery or accumulator variables, e.g. SoC
  • G01R31/3842—Arrangements for monitoring battery or accumulator variables, e.g. SoC combining voltage and current measurements
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
  • G01R31/64—Testing of capacitors

Definitions

• the present invention relates to a resistance measuring device according to the preamble of claim 1.
• Resistance measuring devices of the type discussed here are known in principle. They serve to measure the internal resistance of energy stores, such as the vehicle battery in a vehicle electrical system of a motor vehicle. Such energy storage of a motor vehicle are usually checked for their functioning, by the internal resistance of the respective
• the energy stores to be tested may be permanently installed or possibly also switchable energy stores.
• the internal resistance measurement is necessary for example for voltage sources, such as Super CAP capacitors or conventional vehicle batteries. Internal resistance measurement is particularly problematic for batteries and above all for SuperCAPs of the latest generation because these energy storage devices are designed for particularly high power densities, which require the lowest possible internal resistance. In an energy storage device, which has a very low internal resistance, however, a large current flow is necessary to produce a significant voltage drop. To one
• Another problem is that the measurement of the internal resistance during operation of a connected load by the discharge of the energy storage device must not be falsified. For this purpose, a particularly steep current ramp is required to allow a reliable internal resistance measurement. So that the discharge of the energy storage is not mitge messenger, the current pulse as possible "hard” must be turned on and beyond “soft” be turned off to avoid voltage overloads (load dump) by a sudden power cut.
• Object of the present invention is therefore to provide a resistance measuring device for measuring the internal resistance of an energy storage device that can be used flexibly and reliably measures the internal resistance of the energy storage without falsification of the result by the discharge of the energy storage even with low-resistance designed energy storage.
• the resistance measuring device is used for load-independent measurement of the internal resistance of an energy store, in particular in a vehicle electrical system of a motor vehicle.
• the resistance measuring device is characterized by
• a measuring device for measuring a voltage drop across the
• the resistance measuring device allows the measurement of the internal resistance of an energy storage device independently of the connected load.
• the time of the measurement can be chosen arbitrarily in an advantageous manner.
• a resistance measuring device in which the (passive) component is designed as a storage element, in particular in the form of a capacitor, preferably as an electrolytic capacitor (Elko). It is understood that in principle also other components for generating the (passive) component.
• Self-decaying current pulse can be generated, as long as they are a “hard” switching on and a “soft” off the current pulse
• Energy storage and the device is formed depends on the total resistance of the circuit and the capacitance of the parallel-connected component, if this is designed as a capacitor.
• the switching element is advantageously designed as a MOSFET. Conceivable, however, are also other types of
• the switching element is actuated only when an internal resistance measuring device of the energy storage is to be performed.
• the switching element thus preferably has only the function to allow the implementation of an internal resistance measuring device of the energy storage.
• the measuring device is preferably connected via measuring lines to the energy store and the component and in particular has a
• Microprocessor for calculating the internal resistance of the energy storage is calculated by the detected voltage drop across the energy storage and by a current difference.
• the current difference can be detected via a current measuring resistor, which is preferably switchable between the component and the energy storage.
• a discharge resistor may be connected in parallel with the device.
• the energy supply device has an energy store and a resistance measuring device according to the invention.
• the energy store may have one or more energy storage elements, in particular in the form of so-called SuperCAP capacitors, which are sufficiently known from the prior art.
• the resistance measuring device is not integrated in the load path of the energy store, but is arranged independently of this as a modular separate element, so that a permanent current flow in the resistance measuring device is avoided. This considerably reduces the power loss in the resistance measuring device. Furthermore, results from the present invention, a low load of
• the present invention has the advantage that only a low component cost is necessary.
• FIG. 1 shows a schematic block diagram of a power supply device with an energy store and a resistance measuring device according to the invention
• Fig. FIG. 2 shows a schematic characteristic of the current and voltage differences when carrying out a method according to the invention.
• Fig. 1 shows a schematic representation of a power supply device 1 with an energy store 3 and a resistance measuring device 5 according to the invention.
• the energy storage 3 may consist of one or more energy storage elements, for example, several SuperCAP capacitors or the like energy storage elements. Alternatively, it may also be a conventional motor vehicle battery or the like energy storage.
• the energy storage 3 has an internal resistance Ri and a voltage source 7, which may be connected via corresponding connections to the electrical system of a motor vehicle.
• the resistance measuring device 5 is connected to the energy storage 3. Preferably, it is not integrated in the power path of the energy storage to the electrical system, but arranged separately from this. In this way, a constant current flow through the
• the resistance measuring device 5 comprises a preferably passive component 9, which according to the embodiment according to FIG. 1 is designed as a capacitor and in particular as an electrolytic capacitor (Elko).
• the component 9 is arranged parallel to the energy store 3. Between the energy storage 3 and the component 9, a switching element 11 is provided, via which the energy storage 3 can be short-circuited to the device 9. Parallel to the device 9, a discharge resistor 13 may be provided.
• the resistance measuring device 5 comprises a measuring device 15, which is connected via measuring lines LI, L2 and L3, L4 on the one hand to the energy storage device 3 and on the other hand to the component 9.
• the measuring device 15 is for measuring a voltage drop AU.
• the measuring lines LI and L2 are connected to the energy storage 3. The voltage drop across the energy store can be measured more accurately if the test leads LI, L2 are mounted as close as possible to the terminals "+ Pol" and "-Pol". The same applies to the current measurement explained below, in which also one
• Measuring device 15 for measuring a current difference ⁇ For this is the Measuring device 15 via measuring lines L3 and L4 with a
• the measuring lines L3 and L4 are arranged as close as possible to the current measuring resistor 17 in order to detect the voltage drop across the current measuring resistor 17 with a high accuracy. Thus, when the switching element 11 is closed, a current flows from it
• This current flow is detected by the current measuring resistor 17 and forwarded to the measuring device 15 via the measuring line L3.
• a measurement of the internal resistance Ri of the energy storage device 3 can be carried out at any time independently of a connected load. This is the
• Component 9 is short-circuited. If the component 9, as shown in FIG. 1, is designed as a capacitor, the voltage U applied to the capacitor generates a self-decaying current pulse.
• the electrical behavior of a capacitor in the DC circuit when applying a voltage is well known and should therefore not be carried out further. The only factor is that the connection of the capacitor to the energy storage generates a current pulse with decaying current flow, which is responsible for the
• FIG. 2 shown schematically.
• the time t 0 indicates the time of
• Component 9 continuously increases, resulting from the charging of the Condenser results.
• the current flow I continuously decreases or ends in other words. The more charge is transported, the greater the voltage across the capacitor. According to the ohmic law, the current decreases as a result. In this way, a power cut can be avoided, which would lead to an undesirable voltage increase (load dump).
• the internal resistance Ri of the energy store 3 can then be determined from the measurement of the voltage drop AU and a corresponding current difference ⁇ from the detected measurement curves U and I (see FIG.
• the resistance measuring device 5 enables a load-independent internal resistance measuring device of an energy store 3 in a simple manner. This is achieved, in particular, by designing the component 9 as a capacitor, which naturally generates a defined current pulse when the switching element 11 is switched on.
• the component cost of such a circuit is low and generates only a low power loss. Furthermore, the load of the energy storage device 3 by the resistance measurement with a resistance measuring device 5 according to the present invention can be kept low.
• the current flow does not come about through a connected load, but through the connection of an additional, suitable component 9 connected in parallel to the energy store 3, which generates the self-extinguishing current pulse shown in FIG.
• a passive device that can naturally produce this effect is the capacitor.
• the resistance measuring device 5 can be flexibly used, and especially as additional, retrofittable, modular component with an existing energy storage 3 to form an inventive
• Power supply device 1 are connected.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Measurement Of Resistance Or Impedance (AREA)
• Secondary Cells (AREA)
• Tests Of Electric Status Of Batteries (AREA)

Applications Claiming Priority (2)

Publications (1)

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Citations (3)

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• 2012
  • 2012-02-15 ES ES12155490T patent/ES2762184T3/es active Active
  • 2012-02-15 EP EP12155490.1A patent/EP2629107B1/de active Active
• 2013
  • 2013-02-13 WO PCT/EP2013/052825 patent/WO2013120873A1/de active Application Filing
  • 2013-02-15 US US13/768,951 patent/US9140760B2/en active Active

Patent Citations (3)

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